This invention relates to a bracket which permits effective use of a plastic fastener in joining two panels or other similar articles, and more particularly to a bracket which receives and retains the head of the plastic fastener in position with reference to the weaker of the two panels being joined.
Plastic fasteners are now in general use for attaching trim boards (inner decorative boards) to the inner panels of car doors etc. Although these plastic fasteners come in various types, all comprise at least a head portion, a shank portion extending from the head portion and elastic engaging means provided on the shank portion. With such a plastic fastener, desired union of a trim board with an inner panel in an automobile door has been accomplished by first bringing the head portion of the plastic fastener into secure attachment to a corresponding seat formed in advance on the trim board, then causing at least a part of the shank portion thereof to enter a fitting hole formed in advance at the corresponding position in the inner panel of the door and finally allowing the elastic engaging means on the shank portion to slide past the fitting hole and snap into fast engagement with the opposite edge of the fitting hole.
For use in conventional automobile doors, the inner panels have been naturally made of a metallic material and have therefore enjoyed ample rigidity to withstand the forces acting thereon through the elastic engaging means and, on the other hand, the trim boards have been made of hardboard and the seating portions thereof serving to hold the heads of the plastic fasteners have had high rigidity. The seating portions of the trim boards, therefore, have been capable of retaining the heads of the fasteners in fast attachment thereto even when great force is exerted as if to pull the fasteners out of the seating portions of the trim boards.
In recent years, trim boards made of solid synthetic resin material or foamed synthetic resin material have been widely adopted. Although these boards facilitate fabrication, they are vulnerable to local stress. Still, their material permits easy formation of aesthetically curved surfaces as are required by trim boards of automobile doors and enables arm rests and other accessorial items to be integrally molded with the trim boards. It is because of these merits that the material has come to find wide acceptance.
When a trim board made of such a relatively weak material is attached to a metallic panel, there is a possibility that the seat portion of the trim board serving to retain in position the head of a fastener keeping the trim board attached to the panel will break and the trim board will consequently come off the metallic panel.
An object of the present invention is to provide a bracket for receiving and retaining in position the head of a panel fastener, which bracket is constructed so that even when the panel (trim board) to be kept in contact with the head of the fastener is made of a plastic material or a foamed plastic material and suffers from local weakness, the stress generated where the panel seats the fastener will be dispersed to the extent of precluding the possible breakage of the seat portion.
Another object of this invention is to provide a bracket for receiving and retaining in position the head of a panel fastener which bracket is constructed so as to be easily attached to the back surface of the panel without impairing the appearance of the front surface of the panel.